Twenty-three mutilated corpses were found today near a Syrian protest city seized by regime forces, monitors said, as the regime's bloody crackdown entered its second year to a rising world outcry.

Twenty-three mutilated corpses were found on Thursday near a Syrian protest city seized by regime forces, monitors said, as the regime's bloody crackdown entered its second year to a rising world outcry.

Human rights monitors said the victims had been blindfolded and handcuffed before being shot dead and their bodies dumped outside the northwestern city of Idlib, in an apparent repeat of a similar "massacre" in the flashpoint city of Homs last weekend.

As the Syrian regime and the opposition continued to trade blame for the earlier killings, both sides organised mass demonstrations to mark the first anniversary of the eruption of anti-government protests in the city of Daraa, south of the capital, which was again the scene of deadly violence on Wednesday.

"Twenty-three bodies with marks of extreme torture were found near Mazraat Wadi Khaled, west of the city of Idlib," said the Syrian Observatory for Human Rights in a statement.

It also said at least five others were killed in raids by security forces across the province of Idlib on Thursday and that violent clashes broke out overnight as rebels attacked army posts in the eastern region of Deir Ezzor.

On Wednesday, 37 people were killed in violence across Syria, 20 of them in Daraa, the Britain-based watchdog said.

Human Rights Watch on Thursday demanded an end to the "scorched earth methods" being deployed by President Bashar al-Assad and that China and Russia stop blocking UN efforts to take tough action.

"City after city, town after town, Syria's security forces are using their scorched earth methods while the (UN) Security Council's hands remain tied by Russia and China," HRW's Sarah Leah Whitson.

"One year on, the Security Council should finally stand together and send a clear message to Assad that these attacks should end," said the New York-based group's Middle East director.

Moscow and Beijing have since October blocked two Security Council draft resolutions on the crisis in Syria on the grounds that they were unbalanced and aimed at regime change.

HRW said that "accounts from witnesses reveal significant destruction and a large number of deaths and injuries of civilians in Syria's bombardment of the city of Idlib."

Syrian activists have compiled a list of 114 civilians killed since security forces launched their assault on Idlib, the watchdog said.

The city fell to government forces on Tuesday night, two weeks after the regime stormed the Baba Amr district of Homs in central Syria, following a month-long blitz that activists said left hundreds dead.

Following that offensive, residents of nearby neighbourhoods reported finding the mutilated bodies of women and children. Activists posted video footage they said proved regime forces were to blame.

The government blamed "armed terrorist gangs."

The Damascus government on Thursday renewed its demands for foreign governments to leave Syrians to resolve the crisis by themselves and loyalists held mass demonstrations in the capital and other large cities.

State television showed tens of thousands of people waving Syrian flags and Assad's portrait in cities including Damascus, the second-largest city Aleppo and Latakia, a stronghold of Assad's minority Alawite community on the Mediterranean coast.

"After a whole year of pressure on Syria, we want to make the world hear our voice: Leave Syria in peace," a woman on the street told the state broadcaster.

The authorities, which have blamed the revolt on foreign-backed "terrorist gangs," announced a "global march for Syria" to counter anti-regime demonstrations being organised by the opposition across the world.

"For the lives lost in the battle for Syria," was the slogan beamed across the television screen.

Last week, the Syrian Observatory gave a breakdown of around 8,500 deaths in the past 12 months: apart from 6,200 civilians, it said the toll included more than 1,800 members of Assad's security forces and more than 400 rebels.

In neighbouring Turkey, hundreds of Syrian activists in a "Freedom Convoy" left from the near city of Gaziantep for the border with Syria to mark the one-year anniversary.

"Our goal is to put pressure in our way on the Syrian government to stop its massacres and its embargo on its own people," Moayad Skaif, one of the organisers, told AFP.

France, Syria's former colonial ruler, acknowledged on Thursday that the situation in the country was far too complex to be resolved by a Libya-style armed uprising with outside support.

"The Syrian people is deeply divided and if we give arms to a particular faction of the opposition we could trigger a civil war between Christians, Alawites, Sunnis and Shiites," foreign minister Alain Juppe warned.